We propose to thoroughly define the antigen bovine-associated mucoprotein (BAMP) and its human counterpart HAMP using biochemical and immunochemical methods. Further, we endeavor to unambiguously establish the occurrence of this antigen in normal and neoplastic tissues. Finally, we wish to conclusively establish or disprove that serum antibodies to BAMP (HAMP) can be correlated with certain human pathologies, including neoplasia. If a relationship is established, we will determine whether this phenomena can be of diagnostic value in the detection of cancer. Currently there is some evidence to suggest that BAMP can complex with IgG antibodies and that this combination is non-immunologic. We are pursuing the hypothesis that BAMP is an Fc-receptor for IgG and in an aggregated form can precipitate immune complexes. BIBLIOGRAPHIC REFERENCE: C.L. Martens and J.E. Butler. l977. Purification and characterization of a glycoprotein from human breast cancer cells. Fed. Proc. 36(3):362.